<?php
include("config.php");

// 处理删除请求
if (isset($_GET['delete_id']) && !empty($_GET['delete_id'])) {
    $deleteId = intval($_GET['delete_id']);
    
    // 执行删除操作
    $deleteSql = "DELETE FROM book_list WHERE id = $deleteId";
    if (mysqli_query($connect, $deleteSql)) {
        header("Location: {$_SERVER['PHP_SELF']}");
        exit();
    } else {
        echo "删除失败: " . mysqli_error($connect);
    }
}

// 设置每页显示的图书数量（3行×3列=9本/页）
$booksPerPage = 9;
$currentPage = isset($_GET['page']) ? max(1, intval($_GET['page'])) : 1;
$offset = ($currentPage - 1) * $booksPerPage;

// 查询总记录数
$countSql = "SELECT COUNT(id) as total FROM book_list";
$countResult = mysqli_query($connect, $countSql);
$countRow = mysqli_fetch_assoc($countResult);
$totalBooks = $countRow['total'];
$totalPages = ceil($totalBooks / $booksPerPage);

// 查询当前页的图书数据
$sql = "SELECT id, book_name, img, author, brief, link FROM book_list ORDER BY id LIMIT $offset, $booksPerPage";
$result = mysqli_query($connect, $sql);
$books = [];
if ($result) {
    while ($row = mysqli_fetch_assoc($result)) {
        $books[] = $row;
    }
    mysqli_free_result($result);
} else {
    echo "数据库查询失败: " . mysqli_error($connect);
}


 $defaultImage = "https://picsum.photos/400/600?random=book";
?>

<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>图书管理系统 - 图书列表</title>
    <style>
        body {
            font-family: 'Microsoft YaHei', sans-serif;
            margin: 0;
            padding: 20px;
            background-color: #f8f9fa;
        }
        .container {
            max-width: 1200px;
            margin: 0 auto;
        }
        .header {
            text-align: center;
            margin-bottom: 40px;
        }
        .header h1 {
            color: #333;
            margin-bottom: 10px;
        }
        .pagination {
            display: flex;
            justify-content: center;
            margin-top: 40px;
            gap: 5px;
        }
        .pagination a, .pagination span {
            padding: 8px 12px;
            border-radius: 4px;
            text-decoration: none;
            background-color: white;
            color: #337ab7;
            border: 1px solid #ddd;
        }
        .pagination a:hover {
            background-color: #f5f5f5;
        }
        .pagination .current {
            background-color: #337ab7;
            color: white;
            border-color: #337ab7;
        }
        .book-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 30px;
        }
        .book-card {
            background-color: white;
            border-radius: 8px;
            box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
            overflow: hidden;
            transition: transform 0.3s ease;
            display: flex;
            flex-direction: column;
            position: relative;
            cursor: pointer;
        }
        .book-card:hover {
            transform: translateY(-5px);
        }
        .book-cover {
            width: 100%;
            height: 250px;
            object-fit: cover;
            user-select: none;
            -webkit-user-drag: none;
            -moz-user-select: none;
            -ms-user-select: none;
        }
        .book-info {
            padding: 20px;
            flex-grow: 1;
            display: flex;
            flex-direction: column;
        }
        .book-title {
            font-size: 20px;
            font-weight: bold;
            margin-bottom: 10px;
            color: #222;
        }
        .book-author {
            font-size: 16px;
            color: #666;
            margin-bottom: 15px;
        }
        .book-desc {
            font-size: 14px;
            color: #444;
            line-height: 1.6;
            flex-grow: 1;
        }
        .no-books {
            text-align: center;
            color: #666;
            font-size: 18px;
            padding: 40px;
            grid-column: span 3;
        }
        .delete-btn {
            background-color: #dc3545;
            color: white;
            border: none;
            padding: 8px 12px;
            border-radius: 4px;
            cursor: pointer;
            font-size: 14px;
            margin-top: 15px;
            z-index: 2;
            position: relative;
            transition: background-color 0.3s;
        }
        .delete-btn:hover {
            background-color: #c82333;
        }
    </style>
</head>
<body>
    <div class="container">
        <div class="header">
            <p>共 <?= $totalBooks ?> 本图书</p>
        </div>
        <div class="book-grid">
            <?php
            if (!empty($books)) {
                foreach ($books as $index => $book) {
                    $globalIndex = $offset + $index;
                    $imageUrl = $globalIndex < 6 && isset($firstSixImages[$globalIndex]) 
                        ? ($firstSixImages[$globalIndex] ?: $defaultImage) 
                        : ($book['img'] ?: $defaultImage);
            ?>
                <div class="book-card" onclick="window.location.href='book_detail.php?id=<?= $book['id']; ?>'">
                    <img 
                        src="<?= $imageUrl ?>" 
                        alt="<?= htmlspecialchars($book['book_name']); ?>" 
                        class="book-cover"
                        onerror="this.src='<?= $defaultImage ?>'; this.onerror=null;"
                        oncontextmenu="return false;"
                        draggable="false"
                    >
                    
                    <div class="book-info">
                        <h2 class="book-title"><?= htmlspecialchars($book['book_name']); ?></h2>
                        <p class="book-author">作者：<?= htmlspecialchars($book['author'] ?? '未知'); ?></p>
                        <p class="book-desc"><?= htmlspecialchars($book['brief'] ?? '暂无简介'); ?></p>
                        
                        <button 
                            class="delete-btn" 
                            onclick="if(confirm('确定要删除这本书吗？')) { window.location.href='?delete_id=<?= $book['id']; ?>'; event.stopPropagation(); }"
                        >
                            删除图书
                        </button>
                    </div>
                </div>
            <?php
                }
            } else {
            ?>
                <div class="no-books">没有书籍信息</div>
            <?php
            }
            ?>
        </div>
        
        <div class="pagination">
            <?php if ($currentPage > 1): ?>
                <a href="?page=<?= $currentPage - 1 ?>">上一页</a>
            <?php endif; ?>
            
            <?php for ($i = 1; $i <= $totalPages; $i++): ?>
                <?php if ($i == $currentPage): ?>
                    <span class="current"><?= $i ?></span>
                <?php else: ?>
                    <a href="?page=<?= $i ?>"><?= $i ?></a>
                <?php endif; ?>
            <?php endfor; ?>
            
            <?php if ($currentPage < $totalPages): ?>
                <a href="?page=<?= $currentPage + 1 ?>">下一页</a>
            <?php endif; ?>
        </div>
    </div>
</body>
</html>